XVI INTKODUCTION. 



These comprise a memoir on Cetacea from the Belgian Crag, 

 by Prof. Van Beneden, in the 'Ann. Mus. R. Hist. Nat. Belg.' 

 vol. xiii. pt. 5 (1886), containing figures and descriptions ofAmphi- 

 ceius, Heterocetus, Mesocetus, Idiocetus, and Isocetus ; one by Dr. W. 

 B. Scott, " On some New and Little-known Creodonts," in the 

 ' Journ. Ac. Nat. Sci. Philad.' vol. ix. pt. 2 (1886) ; and a third, by 

 Dr. Burmeister, forming a continuation of the ' Atlas de la Descrip- 

 tion Physique de la Republique Argentine,' Osteologie der Gravi- 

 graden, pt. i. Scelidoiherium and Mylodon (Buenos Ayres, 1886) 1 . 

 In the latter (p. 103) the MS. name Scelidoiherium magnum is 

 revived for S. tarijense (infra, p. 102) ; while the new species Mylo- 

 don oweni 2 (p. Ill) may be identical with M. lettsomi (infra, p. 108). 

 The cranium represented in pi. xiv. figs. 2, 3, as Scelidoiherium 

 leptocephalum appears to belong to S. bravardi (infra, p. 96), and 

 shows (as I thought to be the case) that the length of the nasals is 

 less than half that of the entire cranium. 



July 26, 1887. R. L. 



1 This is the portion of the Atlas alluded to by myself in the ' Proc. Zool. 

 Soc.' 1886, p. 491 ; its publication having apparently been long delayed. 



2 The names applied to these forms by Bravard can hardly be reckoned as 

 more than MS. ones. 



